cleanup and rename provider to plugin

SYS/plugin_config.py

@@ -6,7 +6,7 @@ import pkgutil
 from typing import Any, Dict, Iterable, List, Optional
 
 from SYS.config import global_config
-from ProviderCore.registry import get_plugin_class, list_plugins
+from PluginCore.registry import get_plugin_class, list_plugins
 
 logger = logging.getLogger(__name__)
 
@@ -194,7 +194,7 @@ def get_required_config_keys(item_type: str, item_name: str) -> List[str]:
 
 def get_configurable_store_types() -> List[str]:
     """Return configurable multi-instance plugin types (formerly 'store types')."""
-    from ProviderCore.registry import REGISTRY
+    from PluginCore.registry import REGISTRY
     options: List[str] = []
     for info in REGISTRY.iter_plugins():
         plugin_cls = info.plugin_class
@@ -205,7 +205,7 @@ def get_configurable_store_types() -> List[str]:
 
 def get_configurable_plugin_types() -> List[str]:
     """Return all plugin types that can be configured: those with a schema or MULTI_INSTANCE flag."""
-    from ProviderCore.registry import REGISTRY
+    from PluginCore.registry import REGISTRY
     options: List[str] = []
     for info in REGISTRY.iter_plugins():
         plugin_cls = info.plugin_class